1 files changed, 44 insertions, 0 deletions
diff --git a/spec/ruby/core/hash/fetch_spec.rb b/spec/ruby/core/hash/fetch_spec.rb
new file mode 100644
index 0000000000..f9b80b6c49
--- /dev/null
+++ b/spec/ruby/core/hash/fetch_spec.rb
@@ -0,0 +1,44 @@
+require_relative '../../spec_helper'
+require_relative 'fixtures/classes'
+require_relative '../../shared/hash/key_error'
+
+describe "Hash#fetch" do
+  context "when the key is not found" do
+    it_behaves_like :key_error, -> obj, key { obj.fetch(key) }, Hash.new({ a: 5 })
+    it_behaves_like :key_error, -> obj, key { obj.fetch(key) }, {}
+    it_behaves_like :key_error, -> obj, key { obj.fetch(key) }, Hash.new { 5 }
+    it_behaves_like :key_error, -> obj, key { obj.fetch(key) }, Hash.new(5)
+
+    it "formats the object with #inspect in the KeyError message" do
+      -> {
+        {}.fetch('foo')
+      }.should.raise(KeyError, 'key not found: "foo"')
+    end
+  end
+
+  it "returns the value for key" do
+    { a: 1, b: -1 }.fetch(:b).should == -1
+  end
+
+  it "returns default if key is not found when passed a default" do
+    {}.fetch(:a, nil).should == nil
+    {}.fetch(:a, 'not here!').should == "not here!"
+    { a: nil }.fetch(:a, 'not here!').should == nil
+  end
+
+  it "returns value of block if key is not found when passed a block" do
+    {}.fetch('a') { |k| k + '!' }.should == "a!"
+  end
+
+  it "gives precedence to the default block over the default argument when passed both" do
+    -> {
+      @result = {}.fetch(9, :foo) { |i| i * i }
+    }.should complain(/block supersedes default value argument/)
+    @result.should == 81
+  end
+
+  it "raises an ArgumentError when not passed one or two arguments" do
+    -> { {}.fetch()        }.should.raise(ArgumentError)
+    -> { {}.fetch(1, 2, 3) }.should.raise(ArgumentError)
+  end
+end